Ethylene/carbon monoxide copolymers have been known since at least as early as the 1940s, and their susceptibility to photodegradation has been know since at least as early the 1960s. The use of ECO copolymers in the manufacture of industrial and consumer packaging films has been reported since at least as early as the 1970s, e.g., U.S. Pat. Nos. 3,676,401, 3,929,727 and 4,714,741 and GB 1 448 062. However, notwithstanding the environmental friendly property of photodegradation, these copolymers have not achieved the expected acceptance in industrial and consumer packaging applications because of their less than desirable mechanical properties, particularly tensile and puncture resistance.
WO 91/18944 A1 describes the mixture of the anatase form of TiO2 and a carbon monoxide containing olefin copolymer to enhance photodegradation of plastics and resins. U.S. Pat. No. 6,558,809 B1 describes a film made from substantially halogen free polymers that can be activated with high frequency electromagnetic energy. DE 23 16 697 A1 describes polymers and copolymers containing keto-carbonyl groups which are photodegradable on exposure to ultraviolet radiation. U.S. Pat. No. 4,714,741 describes an ethylene-carbon monoxide copolymer containing about 0.005 to 0.05 percent by weight of carbon monoxide and a low density polyethylene.